Accelerator



AGCELERATOR Filed Nov. 5, 1925 Patented Apr. 14, 1925.'

nomvorn noire; or, 'BELGRADn YUGOSLAVIA.

' Accnnnrca'roa;

ApplicationledNovember 5; 19231 SerialZD-To. 672,965:

To crZZ whom/twintig concern Be itV lnoWntliatI-g DoBmvoJn Bon, a si abject ot the Kingroft Yugoslavia, residing at Belgrade, Yugoslavia; haveinvented new and usefulE Improvements in Accelerators, ol which the followingisaspecification.

In order to avoid dangerousy reactions which are lia-biete' be experienced' when a train lnakedrapidly, tliedepression or drop of'press-ure inj-thet-rainpipeshouid be propaga-ted asfrapidiy as possibletiom the pointoi:l control 1to the `extremity ot ythe-train.

Thisdesideratum is realized byallowing' the air to'escape fromfthetrain pipe either into the atmosphereor in'tothc brake cylinderer into isolatedfchambers-by Wayot socaliedaccelerators: Accelerators which ei;- creise `what may be designated a total f action produce an excessiifefd'i'opo'ffpressure inthe train'piparesultiiigfin-useless Waste of the air and in a braking eifect of constant rapidity acceleratorsl which exercise a partial fand repeated action cannot'l be reliedonto operate iithcertainty.4

An accelerator off oneA of? the best known types V operates as follows :---V

The rapid pressuref-dropN in the train pipe effects' the movement ot'fa'-` piston located` above an isolated chamber..l iilled i with air at the initia'lpressurej bringingzafbout the' openingofl a distributor'unitary with said piston; the action Voff'the` accelerator being interrupted by emptying'theisolatedlchainber.

Vit-h this principle as a'y basis,- notwithstanding that many eti'orts have been made to solve the problemi. practical success has not hitherto 4been realized.` Gertai-nty of? op# eration is only obtainedl when the opening andi closing et? the dstributing member do not take place;` after'- the opening orf closing ot the closedt chamber or space:

In the 'following specification there is described by Wayl of:v example a' construction embodying this principle in which at the end of: its traveltlie accelerator'piston meets a stop and a balanced Valve inthe interior of the v piston continuesL itsftravel under the intluence of its inertia andopens the isolated" chamber' toexhaust; returnv and premature closure being prevente'd by current of air which-v issues from the isolated chamber and impinges on a cap unitary with the valve until the moment when the distributing member closesin consequence of the equalization of pressure.

The evacuation and closure ofthe isolated chamber may be effectedl at the same time asthe closure ot the distributing member, there being employed two yalyes arrangedfto close sinniltaneou-sly.

Two constructions en'ibodying the: ini/'enf t-ionare illustrated in Figs. l' .and lot" the accompanying drawings.

Referring to Fig. 1', there is 'formedl in the-body l of the acceleratora passage 8 connected to the 'main train pipe and conimunicating by Way of passages 7l andy 79 with the ehai'nber. 73 above the accelerator piston @L which separates this chamber from the chamber 'e' The stem tiofthe piston penetrates the base of theV chamber and 'enters tl'iepassage Tl', closing With-thc Valve T7 at'the end oisaid stem the passage'TS leadingto the atmosphere or tothe brake cylinder. spring 79 urges the. piston T4 down` farfls. ln-the interior ot" the piston and of itsstein is seated a Valve 8O the stein 8l ot' which enters the; cavity 82" and is 1" ined as a piston, serringfto balance the rah e when the cavity is connected: with Vthe passa-geil. by way ot the port The part o'fftlic cavity 82 between the valve 8O andits piston comiiiunicates with the chamber 75 by Way oie. the portf Sli and With the isolated space 7E when theV valve Ouistlifted from its seati the upper part of the valve formino `alar-ge can and obstructing almost Y e ,a i v b completely the passage S6.-

Inthe second construction shown dia.- f

grannnatically in Fig. 2-, the `ValVeSOlorms a part ot thevstem 7G of* the pistona and has its seat init-he body-1. The said' Valve closes simultaneously.' with. the' Valve 77.

-rllhe valve 800 controls theexhaust from the chamber returns by the sameroute and; the

acceleratorl does not come into action. Vhen the diminution in pressure iseiiiected With sufficient rapidity and is of suliicient amount, the enclosed air thrusts the piston 74 up'- vinto wardly, so that the valve 7T opens and air passes from the train pipe into the passage 78.

In the lirst constructiom the piston 7a is thrust upwardly until it abuts on the stop, when, in consequence of its inertia, the balancing valveV 80 is unseated and the air passes from the isolated space into the chamber 73; the accelerator piston 74 under the influence of the spring 79 and of the excess pressure acting on the valve 77 commences to descend and closes the valve.

The valve 80 can only engage its seat again when the air current coming from the isolated space is directed against its cap and suppressed.

In the second construction, the two valves open simultaneously. During the ascent ot the piston the pressures above and below the piston balance one another. The piston then commences to descend and closes the two valves simultaneously.

Having now fully described and Vascertained my said invention and the manner in which it is to be performed, I declare that what I claim is Y 1. The combination, with a train-pipe normally containing iluid under pressure, of a casing, aychamber within said casing, a piston within said chamber dividing the same into upper and lower compartments,

spring acting to depress said piston, and a hollow stem for said piston extending down through the bottom wall of said lower co-mpa-rtment, and being formed at its lower end as a valve to control a port in the bottom wall of the casing, said hollow stem having ports communicating with said lowercompartment through which the air therein can escape into said hollow stem and thence into the .upper compartment on the operation of the device, and also having ports communieating with a passage located between the` chamber and the casing which passage is connected with the train-pipe, and a branch of which passage communicates with the upper compartment of the chamber. f

2. The combination, with a train-pipe.

normally containing fluid under pressure, of aI casing, a chamber in said casing, a piston within said chamber dividing the same upper and lower compartments, a spring acting to depress said piston, a hollow stem for said piston extending down through the bottom wall of said lower compartment and being formed at its lower end as a valve to control an exhaustport in the wall of the casing and having ports communicating with said lower compartment, and other ports communicating with a passage located between the chamber and the casing, -which passage communicates with the train-pipe, a branch of which passage also communicates with the upper compartment, a balancing valve located in said hollow stem, a. stem for said valve, and a piston formed on said rod.

8. The combination, with a train-pipe normally vcontaining fluid under pressure, of a casing, a chamber in said casing, a piston within said chamber dividing the same into upper and lower compartments, a spring acting to depress said piston, a hollow stem for said piston extending down through the bottom wall of said lower compartment and being formed at its lower end as a valve to control an exhaust port in the wall of the .casing and having ports communicating with said lower compartment, and other Vports communicating with a passage located between the chamber and the casing communicating with the train-pipe, a branch of which passage also communicates with the upper compartment, a. balancing valve located in said hollow stem, a rod for said valve, and a piston formed on said rod, said first-mentioned ports in the hollow piston stem being adapted to permit the escape of air from said lower compartment into said hollow stem and thence into the upper com- 30 partment'on the opening 'of the balancing valve.

4;. The combination, with a train-pipe normally containing iuid under pressure, of a casing, a chamber in said casing, a piston within said chamber dividing the same into upper and lower compartments, a spring acting to depress said piston, a stop for bringing said piston tok rest before it reaches the top of the upper compartment, a hollow stem for said piston extending down through the bottom wall of said lower compartment and being formed at its lower end as a valve to control an exhaust portin the wall of the casing and having ports communicating with said lower compartment, and other ports communicating with a passage located between the chamber and the casing communicating with the train-pipe,

a branch ot which passage also communicates with the upper compartment, a` balancing valve located in said hollow stem,

a rod for said valve, and a piston formed on said rod, said tiret-mentioned ports in the hollow piston stem being adapted to permit the escapev of air from said lower compartment into said hollow stem and thence into the upper compartment on the opening of the balancing valve.

In testimony whereof I have signed my name to this speciiication.

DoBRivoJE sozio. 

